... , quarry, tunnel 4 long life,fast drill tungsten carbide mine inserts,chisel drill bits:chisel bit features:Products feature: Our ... of GB Advanced Cemented Carbide in China, Zhuzhou Jingzuan Carbide Co., Ltd concentrate on R&D, producing and selling mining ... Administration, Wuhai coal group, Tsitsihar Haitong Group ,Guangxi Debao Copper mine. We enjoy the good reputation in domestic market as well ...